Micro-lens array having color-conversion function, micro-LED display module including micro-lens array, and method for manufacturing micro-lens array

Abstract

The present invention relates to a micro-lens array having a color-conversion function and provided in a micro-LED display module, a micro-LED display module including the micro-lens array, and a method for manufacturing the micro-lens array, An micro-lens array according to an embodiment of the present invention is provided in a micro-LED display module in which micro-LEDs themselves are used as light-emitting materials. The micro-lens array may comprise: a body; bank parts formed to be recessed inward from one surface of the body so as to be in one-to-one correspondence with the micro-LEDs, respectively; lens parts formed to protrude from the opposite surface of the body so as to be in one-to-one correspondence with the bank parts, respectively; a partition wall part formed between the bank parts; and a color-conversion part provided in each of the bank parts so as to convert the color of light emitted from each of the micro-LEDs.

The invention claimed is: 
     
       1. A micro-lens array included in a micro-LED display module using a micro LED as a light emitting material, comprising:
 a body; 
 a bank portion recessed inward from one surface of the body in one-to-one correspondence to each of micro-LEDs; 
 a lens part protruding on an opposite surface of the body in one-to-one correspondence to each of the micro-LEDs; 
 a barrier rib formed between the bank portions; and 
 a color converter included in the bank portion and configured to convert color of light emitted from each of the micro-LEDs. 
 
     
     
       2. The micro-lens array of  claim 1 , wherein the color converter is integrally formed with the body by injecting quantum dot (QD) ink into the bank portion and curing the QD ink. 
     
     
       3. The micro-lens array of  claim 2 , wherein the micro-LED is a blue LED for emitting blue light, and
 wherein the color converter includes: 
 a green converter formed by injecting quantum dot (QD) ink for converting light emitted from the blue LED to green light and curing the QD ink; 
 a red converter formed by injecting quantum dot (QD) ink for converting blue light emitted from the blue LED to red light and curing the QD ink; and 
 a space portion for emitting the blue light emitted from the blue LED without changes. 
 
     
     
       4. The micro-lens array of  claim 1 , further comprising:
 A first light absorption layer formed on a bottom surface of the barrier rib to absorb light incident on the bottom surface of the barrier rib. 
 
     
     
       5. The micro-lens array of  claim 1 , further comprising:
 A light reflection layer formed on a side surface of the bank portion to reflect light emitted to the side surface of the bank portion. 
 
     
     
       6. The micro-lens array of  claim 1 , further comprising:
 a second light absorption layer formed in a region between the lens parts on an opposite surface of the body to absorb the light emitted to the region between the lens parts. 
 
     
     
       7. The micro-lens array of  claim 1 , further comprising:
 an air layer that is recessed in a direction toward the lens part at an edge of a bottom surface of the bank portion and totally reflects light emitted to the region between the lens parts. 
 
     
     
       8. The micro-lens array of  claim 1 , wherein a bottom surface of the bank portion is convex in a direction toward the lens part to allow light passing through the color converter to be condensed to the lens part. 
     
     
       9. A micro-LED display module using a micro LED as a light emitting material and including a substrate with the micro LED, and a micro-lens array provided above the substrate, the micro-lens array comprising:
 a body; 
 a bank portion recessed inward from one surface of the body in one-to-one correspondence to each of the micro-LEDs; 
 a lens part protruding on an opposite surface of the body in one-to-one correspondence to each of the micro-LEDs; 
 a barrier rib formed between the bank portions; and 
 a color converter included in the bank portion and configured to convert color of light emitted from each of the micro-LEDs. 
 
     
     
       10. The micro-LED display module of  claim 9 , wherein the micro-lens array is attached and coupled to an upper part of the substrate by an optical clear adhesive (OCA). 
     
     
       11. The micro-LED display module of  claim 9 , wherein the color converter is integrally formed with the body by injecting quantum dot (OD) ink into the bank portion and curing the QD ink. 
     
     
       12. The micro-LED display module of  claim 11 , wherein the micro-LED is a blue LED for emitting blue light, and
 wherein the color converter includes: 
 a green converter formed by injecting quantum dot (QD) ink for converting light emitted from the blue LED to green light and curing the QD ink; 
 a red converter formed by injecting quantum dot (QD) ink for converting blue light emitted from the blue LED to red light and curing the QD ink; and 
 a space portion for emitting blue light emitted from the blue LED without change. 
 
     
     
       13. The micro-LED display module of  claim 9 , wherein the micro-lens array further includes a first light absorption layer formed on a bottom surface of the barrier rib to absorb light incident on the bottom surface of the barrier rib. 
     
     
       14. The micro-LED display module of  claim 9 , wherein the micro-lens array further includes a light reflection layer formed on a side surface of the bank portion to reflect light emitted to the side surface of the bank portion. 
     
     
       15. The micro-LED display module of  claim 14 , wherein the micro-lens array further includes an air layer that is recessed in a direction toward the lens part at an edge of a bottom surface of the bank portion and totally reflects light emitted to the region between the lens parts. 
     
     
       16. The micro-LED display module of  claim 14 , wherein a bottom surface of the bank portion is convex in a direction toward the lens part to allow light passing through the color converter to be condensed to the lens part. 
     
     
       17. The micro-LED display module of  claim 9 , wherein the micro-lens array further includes a second light absorption layer formed in a region between the lens parts on an opposite surface of the body to absorb the light emitted to the region between the lens parts. 
     
     
       18. A method of manufacturing a micro-lens array included in a micro-LED display module using a micro LED as a light emitting material and including a body, a bank portion recessed inward from one surface of the body in one-to-one correspondence to each of micro-LEDs, a lens part protruding on an opposite surface of the body in one-to-one correspondence to each of the micro-LEDs, a barrier rib formed between the bank portions, and a color converter included in the bank portion and configured to convert color of light emitted from each of the micro-LEDs, the method comprising:
 a mold preparation operation of preparing a first mold having one surface, on which an engraved shape of the lens part is formed, and a second mold having one surface, on which an embossed shape of the bank portion is formed; 
 a mold alignment operation of aligning the first mold and the second mold with each other on a base mold in a state of being spaced apart at a predetermined interval to allow the engraved shape of the lens part and the embossed shape of the bank portion to be arranged in one-to-one correspondence to each other; 
 a polymer injection and curing operation of forming the body including the lens part and the bank portion by injecting transparent polymer into a space between the first mold and the second mold and curing the transparent polymer; and 
 a color converter forming operation of forming the color converter in the bank portion. 
 
     
     
       19. The method of  claim 18 , wherein the micro-LED is a blue LED for emitting blue light, and the color converter includes a green converter configured to convert light emitted from the blue LED to green light, a red converter configured to convert blue light emitted from the blue LED to red light, and a space part configured to emit the blue light emitted from the blue LED without change, and
 wherein the color converter forming operation includes: 
 forming the green converter by injecting quantum dot (QD) ink for converting light emitted from the blue LED to green light into a part of the bank portion and curing the QD ink; and 
 forming the red converter by injecting quantum dot (QD) ink for converting blue light emitted from the blue LED to red light into a part of the bank portion and curing the QD ink. 
 
     
     
       20. The method of  claim 18 , further comprising:
 forming a first light absorption layer on a bottom surface of the barrier rib to absorb light incident on the bottom surface of the barrier rib.